To believe sis(12) over SD(11)?

[Bestofgoodluck]

SD is 11, have been with her dad for 5 years, mum is not involved. DP has to go away often for work and I work from home so look after SD while he’s away. This is mostly been fine, she has the option of staying with grandparents but chooses to stay with me.

I also have a 12 year old sister, our mum has quite a few problems and as I am older, she has stayed with me on and off since she was a baby.

They are completely different but have settled into a friendly but probably not friends relationship and there has never any major problems between them. I have been looking after both a them for about a week. They go to different schools and do different activities so don’t see each other that much but when we’ve been together everything has been fine and they both have seemed happy.

Sister went back to our mums today and SD came to me in tears and showed me some extremely nasty and embarrassing messages sent from my sister to her last night, I comforted her and said I would talk to my sister, she cried for me not to and said just not to make her see her anymore.
Sister said she had no idea what I was talking about and that there were no messages on her phone, was asking what they said and why she would do that, I’m 99% sure I believe her. I was already thinking the wording and content of the messages didn’t seem like things my sister would say and more likely that SD sent them to her self.

I feel completely torn between the two of them and can’t see how I can sort this between them or know who is telling the truth.

AIBU to choose my sister over my stepdaughter? And to say SD has to go to her grandparents if DP is away and my sister wants to stay with me?

I think you have a good understanding of both girls. Firmly but fairly telling them both that they must behave better is good. With such vulnerable situations for both of them it's hard though, I feel for you. Good luck.

I think it's possible to support the feelings while maintaining boundaries around acceptable behaviour. Possibly SD needs support to learn ways to communicate stuff she is upset about/big emotions which aren't behaviours that will cause her more trouble e.g. lying/going on other people's phones

Ok so Dsis is likely to have said a mean thing, I still don’t think that excuses SDs behaviour.

Sneaking around, stealing someone’s phone, lying, then putting on a hysterical performance all to try and banish Dsis from the house. Thats manipulative and way worse than saying a mean thing.

It's obvious you can't be sure who is responsible, so sit them both down together and say if whoever did this doesn't own up and apologise I'm not going to be able to look after either of you SD will go to the grandparents and sister will go back to Mum- it's your choice, and see what they decide- you can't be sure it isn't your sister, thinking she would do it a different way is not evidence, pre teen girls can be very strange, so the only fair thing to do is have neither of them there until this is sorted out.

Unless either child is in danger, I would send them both to their other homes and go and stay by myself and tell them neither is staying till there is an admittance. That the admittance and then a genuine chat between them is the only way forward to either of them staying with you again.

It’s a bit radical and King Solomon like. One of them is lying but you need to question how the situation got so bad.

Plus you not wanting children, having to parent so young has probably meant you have had enough already but feels like the decision was made for you as everyone puts on you.

This is the SD home - it is the OP who has another home. That is I think the crux of the issue

Dp is home and has spoken to sd,
seems some of the comments were said by ‘friends’ at school so that is a separate issue that needs to be sorted out.

my sister has admitted saying certain things claiming she was joking and didn’t realise sd was upset but was quick to want to apologise which she has done by text and hopefully as sd has agreed they will be able to see each other at the weekend and we can sort it out.

Hopefully it's sorted now OP, well done for dealing with it sensibly and sensitively.

That all sounds sensible and like it’s moving in a positive direction, well done Dsis for admitting wrong doing and wanting to apologise.

Has DSD apologised for lying and stealing someone else’s phone? It sounds a bit one sided in terms of taking accountability. That would be a concern for me.

Your latest update sounds very positive , tween / teen girls can be an absolute nightmare so you are not alone .